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Missing assembly reference when using JsonDataSource component


Product Progress® Telerik® Reporting


Error on previewing the report that ulitizes JsonDataSource component.

Error Message

The data provider of type 'Telerik.Reporting.Processing.WebServiceDataSource.JsonDataProvider, Telerik.Reporting.WebServiceDataSource, Version=, Culture=neutral, PublicKeyToken=a9d7983dfcc261be' defined for data sources of type 'Telerik.Reporting.JsonDataSource' cannot be resolved. Are you missing an assembly reference?

Cause\Possible Cause(s)

The usage of the JsonDataSource component which depends on some of the WebServiceDataSource functionalities.


In order to preview reports that utilize JsonDataSource component, it is required to reference the Telerik.Reporting.WebServiceDataSource DLL or the corresponding NuGet package in the application.

The assembly is supposed to be referenced in the project where the Reporting engine runs. If you use the HTML5 Report Viewer or any of its wrappers, this is the Telerik Reporting REST Service project. If you export the report programmatically you should reference the assembly in the project that utilizes the ReportProcessor.

See Also

JsonDataSource Component

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